Roof membranes with removable protective sheets

ABSTRACT

During installation of a single-ply roofing membrane, the surface of the membrane can be protected from dirt, scratches and scrapes by a protective sheet which also provides other beneficial attributes that aid an installer. A roof laminate includes a roof membrane and a protective sheet is removably affixed thereto. The sheet includes at least a first layer directly secured to a second layer. The first layer provides at least one of UV protection, anti-slip, and anti-glare to the roof laminate and so aids the installer in at least one of those respects. The second layer is removably affixed to the roof membrane.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims the benefit of andpriority to U.S. patent application Ser. No. 15/973,955 filed May 8,2018 and is related to U.S. Pat. No. 8,833,037, filed Apr. 5, 2012, andto U.S. Pat. No. 9,163,410 filed Jul. 20, 2014, each of which isincorporated by reference herein in its entirety.

BACKGROUND

Membrane roofs are roofs that are covered with a polymeric sheet ormembrane. These polymeric sheets can be, for example, polyvinyl chloride(PVC), thermoplastic olefin (TPO), or ethylene propylene diene monomerrubber (EPDM), as well as other materials. The polymeric sheet ispositioned over a roof surface and held in place by fasteners, adhesive,or ballast. Adjacent sheets are bonded together along lap seams to forma unitary single sheet of the polymer covering the entire roof.

Generally, roof membranes are either white or black. Theoretically, themembranes could be basically any color. The choice of color may be foraesthetic purposes or to reduce energy costs by reflecting thermalenergy. Regardless of color, the appearance following installation is ofparamount importance both from an aesthetic standpoint and from afunctional standpoint.

When replacing an existing roof, new sheeting is difficult to keepclean. In a re-roofing application, a section of the old roof coveringis removed and new roof membrane is immediately installed in its place.This allows the roof to be fully covered each night. As subsequentsections of the old roof are removed, the roofers walk on the newlyinstalled membrane. This can scratch and mar the new membrane.

While these membranes have generally been commercially successful, thereremains a need for additional improvements to facilitate theirinstallation.

SUMMARY

Embodiments of the present invention are premised on the realizationthat during installation of a single-ply roofing membrane, the surfaceof the membrane can be protected from dirt, scratches and scrapes by aprotective sheet which also provides other beneficial attributes thataid an installer. To those and other ends, a roof laminate to be securedto a roof deck includes a roof membrane that has a first surface and asecond surface and is configured to be secured to the roof deck. Aprotective sheet is removably affixed to the first surface and includesat least a first layer directly secured to a second layer. The firstlayer provides at least one of UV protection, anti-slip characteristics,and anti-glare characteristics to the roof laminate and so aids theinstaller in at least one of those respects. The second layer isremovably affixed to the roof membrane.

In one embodiment, the first layer is configured to provide anti-slipcharacteristics and includes a pattern of raised areas spaced apart byrecessed areas.

In one embodiment, the first layer is configured to provide anti-slipcharacteristics with a static, dry coefficient of friction greater than0.45 and a static wet coefficient of friction greater than 0.6.

In one embodiment, the first layer is configured to provide anti-glarecharacteristics and includes a coating that produces less than 30 glossunits at 60°.

In one embodiment, the first layer is configured to provide UVprotection and includes at least one of an antioxidant, a lightstabilizer additive, and a light reflective pigment.

In one embodiment, one of the first layer and the second layer iscolored and the other of the first layer and the second layer isconfigured to provide UV protection and includes at least one of anantioxidant, a light stabilizer additive, and a light reflectivepigment.

In one embodiment, one of the first layer and the second layer includestext or other indicia.

In one embodiment, the protective sheet is affixed to the roof membraneby a layer of water insoluble adhesive.

In one embodiment, the layer of water insoluble adhesive has apreferential adherence to the second layer as compared to the roofmembrane so that as the protective sheet is removed from the roofmembrane, the adhesive is removed from the roof membrane by theprotective sheet.

In one embodiment, the roof membrane is formed of at least one of PVC,TPO, EPDM, and polyolefin.

In one embodiment, the roof membrane is formed from a polymer selectedfrom the group consisting of at least one of PVC, TPO, and EPDM.

In one embodiment, the roof membrane has a thickness of 40-160 mils.

In one embodiment, the protective sheet includes first and secondperforations along first and second edges of the protective sheet.

In one embodiment, the protective sheet does not cover first and secondedge portions of the roof membrane.

In one embodiment, the protective sheet sticks to the roof membrane inthe absence of a separate adhesive.

According to one aspect of the present invention, a roof laminate to besecured to a roof deck includes a roof membrane that has a first surfaceand a second surface and is formed from a polymer selected from thegroup consisting of at least one of PVC, TPO, and EPDM with a thicknessof 40-160 mils. The roof membrane is to be secured to the roof deck. Aprotective sheet is removably affixed to the roof membrane and includesat least a first layer directly secured to a second layer. The firstlayer is configured to provide at least one of UV protection, anti-slipcharacteristics, and anti-glare characteristics to the roof laminate andso aid the installer in at least one of those respects. A layer ofadhesive is disposed between the first surface and the second layer. Theadhesive is configured to adhere to the second layer when the protectivesheet is removed from the roof membrane.

The objects and advantages of embodiments of the present invention willbe further appreciated in light of the following detailed descriptionand drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of the present invention;

FIG. 2 is a cross-sectional view taken along section line 2-2 of FIG. 1;

FIGS. 3-5 are cross-sectional views similar to FIG. 2 depictingembodiments of the invention;

FIG. 6 is a perspective view of one embodiment of the present inventionduring installation;

FIG. 7 is a cross-sectional view of an edge portion of the embodimentshown in FIG. 6 prior to removal of a protective sheet;

FIG. 8 is a perspective view of one embodiment of the present invention;

FIG. 9 is a cross-sectional view of one embodiment of the invention;

FIG. 10 is a cross-sectional view of one embodiment of the presentinvention; and

FIG. 11 is a perspective view of one embodiment of the presentinvention.

DETAILED DESCRIPTION

To these and other ends and with reference to FIG. 1, a roof laminate 10includes a single ply roof membrane 12 and a release sheet or protectivesheet 14. The roof laminate 10 is to be installed onto a roof, such as aroof deck 16. In that regard, multiple roof laminates 10 may bepositioned in an overlapping relationship (shown in FIG. 6 and describedbelow) during installation of a new roof on the roof deck 16. The roofmembrane 12 includes a first surface 18 and a second surface 20. Thefirst surface 18 faces the roof deck 16 and may contact it duringinstallation, and the second surface 20 is intended to be exposed toweather following installation. The protective sheet 14 includes a firstsurface 22 and a second surface 24, which rests on and covers the secondsurface 20 of roof membrane 12. The protective sheet 14 may be affixeddirectly to the roof membrane 12 or be separated from the roof membrane12 by an adhesive, described below. The protective sheet 14 is intendedto be removed following installation of a new roof and thus protects thesecond surface 20 of the roof membrane 12 during installation of the newroof. Removing the protective sheet 14 exposes the second surface 20 ofthe roof membrane 12. The protective sheet 14 is formed with multiplelayers, each layer providing at least one beneficial characteristicdesigned to aid an installer and is described in detail below.

The roof membrane 12 can be formed from any polymer typically used inroofing applications. These include, by way of example only, polyvinylchloride (PVC), thermoplastic olefin (TPO), ethylene propylene dienemonomer (EPDM), rubbers, polyethylene (PE), polypropylene (PP), as wellas other polyolefins. The roof membrane 12 can have a bottom fibroussurface referred to as fleeceback, which improves bond strength in afully adhered system. The roof membrane 12 is preferably white orslightly off-white, though it can be any color. Embodiments of thepresent invention are most useful when the membrane 12 is a lightercolor, such as white or off-white.

The roof membrane 12 is generally rectangular and can be manufactured toa variety of sizes. By way of example only, the roof membrane 12 can beas narrow as 5 feet to as wide as 40 feet. Length can be from 50 feet to100 feet or more. The roof membrane 12 has a thickness effective for useas a roof cover, for example, from 20 mills to 160 mils thick, and byway of additional example from 40 mils to 160 mils thick. The roofmembrane 12 is water insoluble and designed to withstand naturalenvironmental conditions for prolonged periods of time, for example atleast 15 years.

The multiple layers of the protective sheet 14 are polymeric sheets thatcan be formed from a variety of different polymers. One or all of thelayers may be formed from a non-environmentally degradable polymer.These materials may include any one of the materials listed above forthe roof membrane 12 and also include polyethylene (including lowdensity polyethylene and linear low density polyethylene),polypropylene, polyamide (i.e., nylon), polyester, polyacrylate,polymethacrylate, polyvinylchloride, polyvinylidene chloride, andcombinations thereof.

In one embodiment, and with reference to FIG. 2, the protective sheet 14may include layers 30, 32, which may appear as separate films orcoatings that are stacked upon one another. For example, in FIG. 2, theprotective sheet 14 consists of two layers 30, 32 that are bondedtogether. Each layer 30, 32 may provide the laminate 10 with a differentcharacteristic designed to aid the installer. Although not shown, layer32 may be stacked on layer 30 and so form the surface 22 of theprotective sheet 14. That is, the order of the layers 30, 32 may bealtered depending on the desired attribute of the surface 22. Once theinstallation is complete, the layers 30, 32 are removed.

In one embodiment, the layer 30 may provide color to the protectivesheet 14. Although the protective sheet 14 can be clear, it ispreferable that it be tinted with a color that is distinguishable fromthe color of the roof membrane 12. For example, if the roof membrane 12is white, the protective sheet 14 is preferably any color other thanclear or white, such as green, red, blue or yellow. A pigment or dye maybe added to the layer 30 and/or 32 during its manufacture to provide thecolor for the protective sheet 14. In addition, and with reference toFIG. 6, by way of example, the color may vary across the width of thelayer 30. For example, the layer 30 may include at least two differentcolors. The color in the layer 30 may be utilized to produce text orother indicia or information in the protective sheet 14. As shown, theprotective sheet 14 may include advertising information but may alsoinclude instructions, warranty information, and other text/symbols.

With continued reference to FIG. 2, the other layer 32 of the layers 30and 32 may provide UV protection for the protective sheet 14, and forthe roof laminate 10 prior to removal of the protective sheet 14. Thismay be achieved for a short-term weather resistance, for example, aduration of 1 day to 2 years or until the sheet 14 is removed afterinstallation. UV protection may be obtained by the addition of one ormore antioxidants, UV absorber and light stabilizer additives, and lighteffective pigments to the layer 32. By way of example only, antioxidantsmay include hindered phenols, thiosynergists, hydroxylamines,phosphates, and alpha-tocopherol. Commercially available antioxidantsinclude Irganox® and Irgafos® from BASF; Anox®, Lowinox® and Weston®from Addivant; Songnox® from Songwon; Evernox® and Everfos® fromEverspring; BNX® from Mayzo; Thanox® from Rianlon. In addition, or as analternative, UV protection may be achieved by addition of UV absorbersand light stabilizers, which may include, for example, benzotriazole,hydroxybenzoate, benzophenone, triazine, and hindered amines of variousmolecular weights. These additives are commercially available from BASFunder the brand names Tinuvin® and Chimassorb® and from Solvay under thebrand name Cyasorb®, from Sabo under the brand name SaboSTAB®, fromSongwon under the brand name of Songsorb®, from Mayzo under the brandname of BLS®, from Everspring under the brand name of EverSTAB®, fromRianlon under the brand of Thasorb®, and from Addivant under the brandof Lowilite. In addition, light reflective pigments can be used toscreen UV light, which may include, for example, titanium dioxide. Thesepigments are commercially available as Ti-Pure® from Chemours, asKronos® TiO2 from Kronos, as Tiona® from Cristal, as Troxide® fromHuntsman, and as Tronox® TiO2 from Tronox.

In one embodiment and with reference to FIG. 3, the protective sheet 14may include one or both of the layers 30, 32 described above in FIG. 2.The protective sheet 14 may further include anti-slip layer 34 that isintended to be exposed during installation of the laminate 10 on theroof deck 16. The anti-slip layer 34 is designed to improve traction,particularly with foot traffic. By way of example only, a static, drycoefficient of friction may be greater than 0.45 and a static wetcoefficient of friction may be greater than 0.6. The coefficient offriction measurements may be completed according to the ASTM D1894-14Standard Test Method for Static and Kinetic Coefficients Of Friction OfPlastic Film and Sheeting.

With reference to FIGS. 1 and 3, the anti-slip layer 34 may be formed ina pattern 36 in or on the protective sheet 14, such as a diamond treadillustrated in FIG. 1. In FIG. 3, the pattern 36 may include raisedareas 40 separated by recessed areas 42. This localized relativethickness difference in the anti-slip layer 34 produces a physicaltexturing on the surface 22 of the protective sheet 14. In addition, oras an alternative, the anti-slip layer 34 may include or be formedentirely by rubbery or tacky polymers, such as block copolymers (e.g.,SIS and SBS), amorphous poly-alpha olefin, vinyl acetate/ethylene (VAE)and ethylene-vinyl acetate (EVA). These materials may be formed in auniform coating on the layer 30 or 32 as the anti-slip layer 34 or theymay be formed in discontinuous patterns, such as the raised anddepressed areas 40, 42 in the pattern 36 on the layer 30.

With reference to FIG. 4, in one embodiment of the invention, theprotective sheet 14 may include one or both of the layers 30 and 32described above with regard to FIG. 2 with an anti-glare layer 44forming the surface 22. However, rather than a three-layer protectivesheet 14, as shown, the protective sheet 14 may include one of layers30, 32 and the anti-glare layer 44. The anti-glare layer 44 is designedto reduce reflection of light at any angle of observation that initiallyimpinges on the surface 22. In this way, the installation crew is notexposed to light reflection from the protective sheet 14. The anti-glarelayer 44 may be achieved by increasing surface roughness of the layer30. Alternatively, the anti-glare layer 44 may be produced by a separatecoating on the layer 30, which may be formed by low crystallinitypolymers, such as amorphous poly-alpha olefin, vinyl acetate/ethylene(VAE) and ethylene-vinyl acetate (EVA), acrylic, or silicone. As shownin FIG. 8, the anti-glare layer 44 may include anti-glare regions in apattern on the surface 22. The anti-glare layer 44 may have anintermediate gloss of less than 20 gloss units (GU) when measured at 60°in accordance with the ASTM D2457-13 Standard Test Method for SpecularGloss of Plastic Films and Solid Plastics. In one embodiment, the layer34 or layer 44 may have both anti-slip and anti-glare characteristics inthe above-identified ranges.

With reference to FIGS. 2-4, the protective sheet including one or moreof the layers 30, 32, 34, and 44 may be made by co-extrusion,co-blowing, or a lamination process.

As shown in FIG. 5, a thin layer of a water-insoluble adhesive 46 may beapplied between the second surface 20 of the roof membrane 12 and thesurface 24 of the protective sheet 14 to adhere the two together. Theadhesive 46 may be clear and have a preferable adherence to theprotective sheet 14 as opposed to the roof membrane 12. In this way,when the protective sheet 14 is removed, the adhesive 46 is alsoremoved. The surface 20 is thus left dirt and adhesive free. Waterinsoluble adhesives may include acrylic based, natural rubber-based,butyl rubber-based, styrenic block copolymer based, ethylene-vinylacetate based, amorphous poly-alpha olefin based and silicone basedadhesives.

The roof laminate 10 is formed by separately forming the roof membrane12 and the protective sheet 14, and laminating the two together. If thelaminate 10 includes the adhesive 46, the adhesive 46 can be formed byco-extruding a pressure sensitive adhesive along with the membrane 12,or subsequently coating the membrane 12 with a pressure sensitiveadhesive, in particular a thermoplastic pressure sensitive adhesive. Inone embodiment, the laminate 10 is adhesive free (FIG. 2). In thatregard, the protective sheet 14 can also be made naturally adherent tothe membrane 12 by incorporating tackifiers into the protective sheet14, such as into layer 30 or 32, and applying the protective sheet 14 tothe membrane 12 in a slightly stretched condition which liberatestackifier. The exposed tackifier provides weak adhesion of theprotective sheet 14 to the membrane 12. Once the protective sheet 14 islaminated to the membrane 12, the roof laminate 10 is formed into a roll38.

To apply the roof membrane 12 over the roof deck 16 and with referenceto FIGS. 6 and 7, two adjacent roof laminates 50 and 52 are laid downside by side over the roof deck 16. The roof membrane 12 of firstlaminate 50 is fixed to the roof deck 16, generally using adhesives (notshown) or fasteners (not shown). The second roof laminate 52 is rolledout and adhered to the roof deck 16 adjacent the first laminate 50 withan edge 54 of the second laminate 52 overlapping an edge 56 of the firstlaminate 50. The overlapping edges 54 and 56 are adhered or welded toeach other.

With the embodiment shown in FIGS. 6 and 7, an edge portion 60 of theprotective sheet 14 on the first roof laminate 50 is pulled up enough toallow an edge 62 of the second protective sheet 14 to overlap theexposed edge 56 of the first laminate 50. The overlapping edges 54 and56 are then bonded together by heat or adhesive. As shown in FIG. 7, theedge portion 60 of the protective sheet 14 from the first roof laminate50 is then folded back and rests over an overlapped portion 64 of thetwo membranes 12.

As shown in FIG. 1, the protective sheet 14 covers the entire roofmembrane 12 from edge to edge. However, as shown in FIG. 9, theprotective sheet 14 may cover the entire membrane except for 4- to12-inch portions on either edges 66 and 70 of the roof laminate 10.Alternatively, as shown in FIGS. 1 and 10, the protective sheet 14 caninclude an overlap region 72 at which two separate protective sheets 14may be bonded together.

In FIG. 11, perforations 80, 82 may be formed alongside edges 84 and 86.The perforations 80, 82 allow strips 90 and 92 to be removed from theprotective sheet 14 leaving the field portion 94 of the protective sheet14 protecting the membrane 12. These embodiments allow adjacent rooflaminates 10, and in particular the adjacent membranes 12, to be bondedtogether while the field portion 94, shown in FIG. 11, remains on themembrane 12.

Once the roof is fully installed, all of the protective sheets 14 arepulled away from the membrane 12 leaving an exposed white or coloredmembrane surface free of scratches and dirt.

While the present invention has been illustrated by a description ofvarious embodiments and while these embodiments have been described insome detail, it is not the intention of the inventors to restrict or inany way limit the scope of the appended claims to such detail. Thus,additional advantages and modifications will readily appear to those ofordinary skill in the art. The various features of the invention may beused alone or in any combination depending on the needs and preferencesof the user.

What is claimed is:
 1. A roof laminate to be secured to a roof deckcomprising: a roof membrane that has a first surface and a secondsurface and is configured to be secured to the roof deck; and aprotective sheet that is removably affixed to the first surface andincludes at least a first layer directly secured to a second layer, oneof the first layer and the second layer includes text or other indiciaand the second layer is removably affixed to the roof membrane.
 2. Theroof laminate of claim 1 wherein one of the first layer and the secondlayer is colored.
 3. The roof laminate of claim 1 wherein the firstlayer includes a pattern of raised areas spaced apart by recessed areas.3. The roof laminate of claim 1 wherein the first layer has a static,dry coefficient of friction greater than 0.45 and a static wetcoefficient of friction greater than 0.6.
 4. The roof laminate of claim1 wherein the first layer includes a coating that produces less than 30gloss units at 60°.
 5. The roof laminate of claim 1 wherein the firstlayer includes at least one of an antioxidant, a light stabilizeradditive, and a light reflective pigment and is configured to provide UVprotection.
 6. The roof laminate of claim 1 wherein the protective sheetis affixed to the roof membrane by a layer of water insoluble adhesive.7. The roof laminate of claim 6 wherein the layer of water insolubleadhesive has a preferential adherence to the second layer as compared tothe roof membrane so that as the protective sheet is removed from theroof membrane, the adhesive is removed from the roof membrane by theprotective sheet.
 8. The roof laminate of claim 1 wherein the roofmembrane is formed of at least one of PVC, TPO, EPDM, and polyolefin. 9.The roof laminate of claim 1 wherein the roof membrane is formed from apolymer selected from the group consisting of at least one of PVC, TPO,and EPDM.
 10. The roof laminate of claim 9 wherein the roof membrane hasa thickness of 40-160 mils.
 11. The roof laminate of claim 1 wherein theprotective sheet includes first and second perforations along first andsecond edges of the protective sheet.
 12. The roof laminate of claim 1wherein the protective sheet does not cover first and second edgeportions of the roof membrane.
 13. The roof laminate of claim 1 whereinthe protective sheet sticks to the roof membrane in the absence of aseparate adhesive.